Firefighters wear protective coats and trousers to shield their bodies from heat, flame, liquid penetration, and from other hazardous conditions that a firefighter may encounter while fighting a fire. These protective garments are typically made in layers beginning at the interior with a thermal inner liner provided to insulate the firefighter's body from heat penetration; next a moisture barrier provided to repel liquids, particularly water used to extinguish or suppress the fire, and for preventing such liquids from reaching the firefighter's body; and next an outer protective shell provided to act as a primary shield against flame, heat, debris and other hazardous exposures present at a fire.
The outer protective shell also acts as the functional outer surface of the garment. It provides a surface for reflective trim for visibility and for the attachment of pockets, hooks, straps, etc. for carrying the equipment needed to perform firefighting duties. Consequently, the outer protective shell is both the sacrificial outer layer of protection and the most complex and expensive element of the firefighter's multilayered garment.
In recent years, and largely because of the rapid improvement in protection offered by better materials and designs, the amount of flame and extreme heat exposure typically experienced by a firefighter has increased. In specific cases, tactics have been modified to approach a fire very rapidly and aggressively. These tactics greatly increase the exposure of the outer shell to heat and direct flame. Two factors are immediately impacted. First the outer shell typically is at least partially consumed by flame and heat significantly faster, and is consequently damaged with higher frequency and cost. Second, the greatly increased heat penetrates significantly more rapidly to the interior, which if not compensated for can cause extreme discomfort or burn injury to the firefighter.
The historic and current response to these two key factors has been to provide outer protective shell materials that can take more and longer flame exposure, and to provide extra thermal protection either under the outer protective shell and the inner thermal lining component, or both.
Outer protective shell fabrics have been improved, increasing resistance to flame from instant deterioration to limited delayed deterioration, prolonging disposal of the outer shell substantially. But, insofar as is presently known, no fabric has yet been introduced for standard issue which could sustain direct flame contact indefinitely, without deterioration. And when deterioration finally reaches a point where repair or replacement of the outer protective shell becomes necessary, the most complex and expensive component--the outer protective shell--must be retired from service.
It is important to note that the highest level of exposure on the firefighter's protective garment occurs where the heat is concentrated. In a burning structure, heat rises and concentrates in strata in the structure, very predictably. If the temperature at the ceiling of a fire-involved structure has reached 800.degree.-1000.degree. F. (typical in a residential or commercial structure), then the heat will have stratified at about 650.degree. F. at standing head height (top of doorway), and will drop to 250.degree. at 44" (kneeling head height). Floor temperatures will typically remain at 150.degree. F.
When an aggressive fire attack is made, firefighters will move upright, but crouched, through the hotter strata, exposing their heads and upper torsos to the higher heat and the more frequent flame exposures that exist at this level. Consequently, there is typically a need to focus the extra flame and thermal protection in the upper portion of the outer protective shell.
Accordingly, there exists a need in the firefighter's multilayer protective garment art for an additional garment that can be worn over the outer protective shell needing additional flame and thermal protection and which garment can be removed when such additional flame and thermal protection is not needed.
More particularly, this invention is an improvement to the invention of U.S. Pat. No. 4,507,806 entitled Protective Garment, patented Apr. 2, 1985, Christopher E. Coombs inventor, assigned to Cairns & Brother Inc., the assignee of the present invention; this patent is hereby incorporated herein by reference as if fully reproduced herein and is hereinafter referred to as the "'806 patent."
The protective garment of the '806 patent includes a protective outer shell 12 and an inner thermal liner 34 worn under the outer protective shell. As described in the '806 patent and shown in FIG. 1 of its drawings, the outer protective shell 12 includes a neck opening 24 surrounded by a collar or annular tab 22 provided on its outer surface 26 with a VELCRO.RTM. fastening material strip 28 and provided on its inner surface 30 with a VELCRO.RTM. fastening material strip 32. The inner thermal liner 34, FIG. 2 of the '806 patent, includes a neck opening 24a surrounded by a collar 44 provided with a circumferential outer flap 46 extending downwardly from the Circumference of an upper collar edge 48; the outer and inner surface of the collar 44 is provided with a VELCRO.RTM. fastening material strip 54 and the inner surface of the outer flap 46 is provided with a strip 52. These VELCRO.RTM. fastening material strips, as taught in the '806 patent and as illustrated in FIG. 3 of the '806 patent, provide interconnecting means for interconnecting the collars of the outer protective shell 12 and the inner thermal lining 34 which both interconnects such collars and provides a visual indication that the thermal inner liner has been assembled to the outer shell and is being worn by the wearer, e.g. firefighter, of the outer shell and inner liner. This visual indication, as taught in the '806 patent, is provided by the outer collar flap 46 of the inner thermal liner 34 which obscures from view the collar or annular tab 22 of the outer shell 12 which collar 22 is made, for example, and as taught in the '806 patent, of a bright fluorescent material contrasting with the remainder of the outer shell and which bright material is obscured from view upon the flap 46 of the inner liner collar 44 being fastened over the collar or annular tab 22 of the outer protective shell 12. Generally, and as taught in the '806 patent, the protective outer shell 12 is designed primarily to shed water and the inner thermal liner 34 is designed primarily to provide the wearer, e.g. firefighter, with thermal insulation. The inner thermal liner 34 may include a moisture barrier layer, such as moisture barrier 42 shown in FIG. 2 of the '806 patent.